Domestic refrigerator



Filed March 6, 1939 CQG. VRETMAN DOMESTIC REFRIGERATOR Patented Oct. 7, 1941 DOMESTIC nEFarGEnA'roa can c.. vretma'n, Atlanta', Ga. Appucaon March 6, 1939', serial No. 260,143 'z claims. (c1.l cs2-95) This invention relates to refrigerators, particularly of the type used for household purposes, and has for a p ry object to provide an extremely simple arrangement of the cooling elements in the housing which will divide the inside of the chamber or box into a plurality of com- ,A partments which, by'reason of the relative location of the cooling elements, will tend tomaintain said compartments at different relative tem peratures.

' Another object of the invention is to provide.

a freezing unit which will not require a drip pan i to catch such small quantity of moisture of condensation as may occur, and in which said moisture, if any, will not fall upon the contents of the refrigerator but will run down the side walls.

front and supported above a compartment 3 for the refrigeration mechanism indicated generally by numeral 4. The refrigeration mechanism may be of any suitable type, such as a conventional mechanical compression and expansion type, or a gas absorption type. As the present invention does not directly concern the mechanism for compressing the refrigerant, this mechanism need not be particularly described herein, but is diav grammatically represented in the drawing as a conventional mechanical unit' comprising a compressor, a condenser, a receiver, and connections for conducting the refrigerant to an expansion A further object of this invention is to proclosed, are completely and tightly sealed from each other so as to prevent interchange of atmosphere and temperature exchange, but which, when the door is open, will be open for free access thereto.

A further object of this invention is to provide a refrigerator having a plurality of compartments, one of which is a freezing compartment,

in which the food compartments are cooled by thev same cooling elements as thefreezing compartment, but in which the atmosphere and humidity of the food compartments will nothave access .to the freezing compartment, whereby frosting of the freezing compartment and drying of the atmosphere of the food compartments are reduced.

A still further object of the invention is to providea freezing unit of la type which can be cleared of frost or ice or other adhering matter quickly and conveniently by scraping substantially plane, smooth surfaces and without the necessity of putting the refrigerating apparatus out of 'operation.

'An embodiment serving to illustrate the invention is shown in the accompanying drawing, in

which i y Fig. 1 is a side sectional view of the refrigerator; and i? Fig. 2 issn elevational sectional view.

In the drawing, numeral I indicated generally an insulated box having a door 2 atth'e valve 5 located in close proximity to the cooling elements I and 8. The 'cooling elements 1 and 8 may comprise evaporators 9 and III in the form of flat coils or else vacuum plates of more or less conventional character per se and liquid heat transfer plates I3 and l,Il located on the top and bottom of the upper and lower evaporators 9, IIJ respectively. The evaporators are preferably connected in series, and one of said evaporators, for instance, the lower evaporator 9, receives the expanding refrigerant from the expansion valve 5,

and from said lower evaporator 9 the refrigerant passes through Il to the upper evaporator Il, from which it then passes through return pipe I2 back to the compressor or the like.

The compartment 23 between the cooling elements 'I and 8 constitutes the coldestcompartment of the refrigerator, which is used for making ice or frozen deserts, for keeping meat, or for other purposes where low temperatures are required. Freezing trays I 'I are shown in the freezing compartment 23 in broken lines.

The liquid heat transfer plates are entirely closed and ilt closely against the side and back walls of the refrigerator box and may be soldered f or otherwise integrally connected with the walls so as to. prevent air or liquid from passing between their edges and the walls, and may be soldered tothe evaporators to prevent moisture fromgetting therebetween. The liquid plates are filled with a liquid which will not freeze at the 'temperature to which it is to be subjected. At

the front edges of the vacuum plates and liquid plates, resilient packings such as rubber strips It is apparent that along the surfaces of the vacuum plates the portions closely adjacent an interior pipe will be colder than the portions adjacent the spaces or gaps between theinterior pipes. This is undesirable, as it would cause freezing of iceA or frost in ridges. alongthe coldei`- ments which include the vacuum plates and liquid plates which are smooth and substantially plane on their surfaces. However, the lower surface of the lower liquid plate is preferably made to slope slightly downwardly from a central line toward the sides (Fig. 2) so that moisture of condensation or melted frost, if any, will run tothe sides instead of dropping upon the contents of the lower compartment.

'I'he walls of the freezing compartment are located in the refrigerator at any desired location depending principally upon the relative temperatures desired to be maintained in the upper and lower compartments. If it is desired that the upper compartment be-colder than the lower compartment, the division walls constituted by the cooling elements and liquid plates should be located considerably closer to the top than to the bottom. The upper compartment thus being the smaller requires less cooling to attain the lower temperature but, due to the fact that heat tends to rise, the eiciency of heat transfer from the lower compartment to the lower liquid plate is higher than from the upper compartment to the upper liquid plate. This tends tomake the lower compartment the colder so that it is necessary that thev upper compartment be made even smaller than would otherwise be the case, in order that it shall have the lower temperature of the two. It will be observed that in the illustrated embodiment the upper compartment is shown as being only about half the size of the lowerl compartment. 'I'hls relation of sizes can be varied at will and if it is desired that the lower compartment be the colder, it is only necessary to arrange the cooling elements at a lower position.

In operation the freezing compartment, being located directly between the two vacuum plates 9 and i0, is maintained at a low temperature for freezing its contents. The upper compart 2l being comparatively small is the neXt coldest compartment. The oor of this comthe lower compartment 22 is cooled byliquid plate i4 in contact with vacuum plate IG, serves to cool the compartment, and the liquid plate 4serves to make the temperature uniform over the entire area of the fioor. As the upper surface of the liquid plate is smooth, accumulations of frost, if any, may be scraped olf the plate so that it will hardly ever be necessary to turn off the refrigeration apparatus for defrosting. In a similar way the lower compartment 22 is cooled by liquid plate i3, but the compartment 22 being larger than the upper compartment is maintained at a higher temperature. However, the 'relative temperature can be changed by changing the position of the cooling elements so that the relative sizes of the compartments is changed. If moisture should ever be present on the lower face of liquid heat transfer plate I3, it will run to the sides and down the side walls instead of dropping upon aangaat the contents of the compartment, this actiii being due to the lateral downward slope of the lower face of said plate.

In the embodiment illustrated two evaporators connected in series have been disclosed, but, if desired, one of these may beomitted, in which y case a liquid heat transfer plate or a plain sheet metal plate will serve as the partition for the freezing compartment.

Furthermore, as a further alteration, one or both of the evaporators may extend only partially across the chamber, but in this case the liquid or metal heat transfer plates should extend the entire width and serve as the partitions.

I claim as my invention:

1. In a domestic refrigerator, walls forming a chamber, a cooling element in said chamber dividing off a part of said chamber as a freezing compartment while the remainder serves as a cold storage compartment, said cooling element comprising an evaporator in the form of a fiat plate toward the freezing chamber and a fiat container entirely close'd from and free of the refrigerant and being filled with liquid which will not freeze at the temperature to which it is to be subjected, said container being located on the side of the evaporator plate toward the cold storage compartment for distributing the cooling eect of the evaporator and retarding heat transfer from the cold storage compartment to the evaporator.

2. In a domestic refrigerator, wall-s forming a chamber, a cooling element in said chamber dividing off a part of said chamber as a freezing compartment while the remainder serves as a cold storage compartment, said cooling element comprising an evaporator in theform of a fiat plate toward the freezing chamber and a fiat container entirely closed-from -and free ofthe refrigerant and being filled with -liquid which will not freeze at the temperature to which it is to be subjected, said container being located on the side of the evaporator plate toward the cold storage compartment for distributing the cooling effect of the evaporator and retarding heat transfer from the cold storage compartment to the evaporator, the adjacent surfaces of said evaporator and liquid container being integrally `united to improve heat transfer and prevent Water or ice from entering therebetween.

3. In a domestic refrigerator, walls forming a chamber, a cooling element in said chamber dividing off a part of said chamber as a freezing compartment while the remainder serves as a cold storage compartment, said cooling element comprising an evaporator in the form of a flat plate toward the freezing chamber and a fiat container entirely closed from and free of the refrigerant and being filled with liquid which will not freeze at the temperature to which it is' to be subjected, said container being located on and lower storage compartments above and beences in the cooling surfaces of the cooling ele-- ments.

5. In a refrigerator, walls and a door formingl a chamber, a pair of flat cooling elements ex-` tending horizontally entirely across the chamber ments above and below respectively, said cooling elements comprising flat evaporators and liquidcontaining chambers adjacent said evaporators on the sides thereof adjacent the upper and and spaced apart from each other so as to form a freezing compartment therebetween and -upper and lower storage compartments above and below respectively, said cooling elements comprising evaporators and liquid-containing chambers adjacent said evaporators onthe sides thereof adjacent the upper and lower compartments respectively for eliminating temperature differences in the cooling surfaces of the cooling elements, the bottom surface of the lowerv liquid chamber sloping downwardly laterally from a central line to cause condensate to iiow to the sides and downvthe walls instead of dropping upon the contents of the lower compartment.

6. In a refrigerator, .walls and a door forming a chamber, a pair of fiat cooling elements extending substantially horizontally entirely across the chamber. andspaced apartl from* each other so as, to form a freezing compartment therebetween and upper and lower storage compartlower compartments respectively for eliminating temperature differences in the cooling surfaces of the cooling elements, said liquid chambers being tightly sealed at their edges against the side walls and back, and elastic sealing strips at the door edges of said chambers for sealing against the door when closed,l whereby water vapor from food in the upper and lower compartments is prevented from reaching the freezing compartment. y A

7. In a refrigerator, walls and avdoor forming a chamber, a pair of iiat cooling elements exy tending horizontally entirely across the chamber and spaced apart from each other so as to form4 a freezing compartment therebetween and upper and lower storage compartments above and below respectively,'said cooling lelements comprising liquid-containing chambers on the sides vthereof adjacent the upper and lower compartments respectively for eliminating temperature di'erences in the surfaces of the cooling elements toward said storage compartments,V said cooling elements having smooth and substan-A tially plane free surfaces from which frost may be scraped. l

ARL IviuivrMAN.` 

